Coaxing Fresh Water from Beneath Arizona’s Desert Sand

Yuma is 75 miles away from the nearest sea, which makes it an unlikely spot to find a water desalinization plant.

But in 1992, the Yuma Desalting Plant went online to remove salt from agricultural runoff, and increase the supply of fresh water in the Colorado River.
Severe flooding shut down the plant a few months later and it’s been mothballed for almost all of its 25-year history.
Chuck Cullom, Colorado River programs manager for the Central Arizona Project, says the plant may have a new life freshening up the state’s brackish groundwater that otherwise is too salty to drink.
“We think that brackish groundwater resources can increase the reliability of existing water supplies, and provide new water supplies for the state of Arizona,” he states.
It’s more than a drop in the bucket. Experts have identified six major sources of brackish groundwater across the state – enough to supply fresh water for 400,000 to 600,000 homes.
But getting started is expensive. The U.S. Bureau of Reclamation, which operates the Yuma plant, says getting it back online will cost $30 million to $50 million.
Brackish water is less salty than seawater, and can be treated with traditional technology at one-third the cost.
Then there’s the question of what to do with the leftover brine.
Collum says the state is trying to figure out how to prevent the brine from contaminating other water sources.
“So we want to protect our high quality aquifers from salt, from making them too salty to use or requiring new ‘desal’ efforts,” he states.
Collum sits on a special committee studying the future of desalinization in Arizona. It’s expected to issue a report by the end of the year.